Exceptions to Hess's Law

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Amy Kumar 1I
Posts: 114
Joined: Thu Jul 11, 2019 12:15 am

Exceptions to Hess's Law

Postby Amy Kumar 1I » Sun Jan 26, 2020 12:44 pm

Are there any situations where you would not be able to simply "add" chemical reactions together to determine overall delta h?

Tyler Angtuaco 1G
Posts: 130
Joined: Wed Sep 11, 2019 12:16 am

Re: Exceptions to Hess's Law

Postby Tyler Angtuaco 1G » Sun Jan 26, 2020 12:54 pm

Probably only when your adding reactions that don't involve common molecules or elements, such as if one molecule or element is present in one reaction but not the other(s). This is likely the case since heat of formation will be different with molecules or elements of different bond energies. I don't suspect any other cases.


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